Air Pressure Switch (Aps) X3-02 - Siemens LMV37.4 Series Basic Documentation

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7.3.5 Air pressure switch (APS) X3–02
Input for connection of an air pressure switch. Air pressure is anticipated when the fan is
switched on. If there is no air pressure signal, the system initiates lockout. The air
pressure switch must have an NO contact.
If no air pressure switch is required (e.g. when firing on oil), a wire link to the fan output
must be fitted (between X3-02, pin 1, and X3-05, pin 1).
Caution!
The OEM must check to see whether the burner can be operated without air
pressure switch. This may necessitate a special approval, depending on the
type of application.
"L" for air pressure switch (LP)
Air pressure switch (LP)
Figure 13: Air pressure switch (APS) X3-02
No. Parameter
235 Air pressure switch
1 = active
2 = active, except phase 60...66 (pneumatic operation only)
Error Diagnostic Meaning for the LMV37.4... system
code code
3 0 Air pressure off
1 Air pressure on
4 Air pressure on – start prevention
For the input, a repetition counter can be parameterized. Here, it is possible to set the
number of errors that are permitted until lockout occurs (refer to subsection Repetition
counter).
No. Parameter
196 Repetition limit air pressure failure
1 = no repetition
2 = 1 repetition
Basic documentation LMV37.4...
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20.09.2013